The purpose of the Animal Model Core (Core D) is to provide a centralized facility in which all of the various animal models of asthma outlined in the Program Project may be performed. Personnel experienced in implementing murine models of asthma in a rigorous and reproducible manner will staff the core. All three Projects will utilize Core D. The main responsibilities of the core will be the performance of and analysis of data from murine models of asthma. Specific activities will include: Antigen sensitization and challenge, Measurement of Airway Hyperresponsiveness, Analysis of bronchoalveolar lavage (BAL), Harvest and processing of murine tissue samples. Ensure appropriate storage and inventory of processed murine samples and coordinate their distribution to investigators within the Asthma PPG